
#include<stdio.h>
 
int Add(int a, int b)
{
	return a + b;
}
int Sub(int a, int b)
{
	return a - b;
}
int Mul(int a, int b)
{
	return a * b;
}
int Div(int a, int b)
{
	return a / b;
}
 
void menu()
{
	printf("****************************\n");
	printf("***** 1.add      2.sub *****\n");
	printf("***** 3.mul      4.div *****\n");
	printf("******     0.exit      *****\n");
	printf("****************************\n");
}
int main()
{
	int input = 1;
	int x = 0;
	int y = 0;
	int ret = 0;
	while (input)
	{
		menu();
		printf("请选择：");
		scanf("%d", &input);
		if (input >= 1 && input <= 4)
		{
			printf("输入两个数：");
			scanf("%d%d", &x, &y);
		}
		switch (input)
		{
		case 1:
			ret = Add(x, y);
			break;
		case 2:
			ret = Sub(x, y);
			break;
		case 3:
			ret = Mul(x, y);
			break;
		case 4:
			ret = Div(x, y);
			break;
		case 0:
			printf("退出\n");
			break;
		default:
			printf("输入错误\n");
			break;
		}
		printf("ret = %d\n", ret);
	}
	return 0;
}
